Broadcast radio is essentially a one to many medium where music is curated by station programming directors and sent to listeners via their tower. Streaming music is different in that anyone can stream music, but the plays of streaming audio are treated differently from a copyright use perspective. This is why broadcast radio has not completely shifted into streaming.
Consumers want to avoid commercials and they have a number of options to obtain commercial free music. That said, only so many people want to pay the fees for these services and only so many people want to do the work to build playlists, discover music, etc. The vast majority of consumers would prefer to just play a radio station and skip to another station when they hear a song they don't like or when a commercial stop set plays. As a result, many broadcasters have coordinated their commercial stop sets to be played at the same time.